This invention relates to a fireplace accessory and, more specifically, to a device for improving the efficiency of burning of logs and other comparable fuels, such as paper logs, artificial logs, charcoal, lignocellulosic and carbonaceous fuels, and other fossil fuels, but most preferably as when burning logs in a fireplace of the wood-burning type.
Myriad devices have been proposed for relocating or confining the combustion normally occurring in a fireplace, such as by moving the combustion zone outwardly from the fireplace within an enclosed chamber from which improved radiation may be obtained. A well-known example of historic origin is the Franklin stove.
Still other proposals have been made for enshrouding, partially enclosing, or otherwise providing heating chambers in or surrounding the fireplace chamber, mantle, or grate.
Arrangements have been proposed, too, for positioning combustible fuel, such as logs, in such a way (as by stacking of logs) that air is more likely to be made available to the logs for combustion or so that radiating surfaces of the burning logs are oriented toward the fireplace opening.
Other devices have involved the use of various forms of ducting, such as using large tubes shaped in the form of a grate to permit air to be drawn into the fireplace through the tubes, heated, and discharged from opposite ends of the tubes into the adjacent room.
The foregoing devices fail in various ways to enhance the combustion efficiency of typical fireplace fuels, i.e., logs, newspaper rolls, etc. Many such lignocellulosic fuels contain volatiles which cause production of off-gases rising uselessly up the fireplace. More objectionably, they may be deposited as tars, condensates and soot in the chimney, causing a fire risk and necessitating periodic chimney cleaning.
Among the prior art also must be noted the use of a heavy cast iron plate called a "fireback" for lining the back of a fireplace, such plate being typically upright and also being heated as fuels are being burned in the fireplace. The term "arch" has been applied to an ignition tunnel of insulative brick through which coal is conveyed to a boiler combustion chamber, the brick causing the coal to be more quickly brought up to ignition temperature.
Among problems of such prior art devices include the failure to permit the heat achieved during combustion to be radiated outwardly from the zone of combustion in an efficient, focussed, or useful way, whereby a disproportionate, wasteful quantity of the heat generated by the process of combustion within the fireplace is irretrievably lost up the chimney.
Ordinary fireplace grates, cradles, firebacks, inserts and the like do not typically facilitate lighting or ignition of logs or do not necessarily make it easier to get a fire started. But this is particularly so if one is attempting to ignite a single log. It is common knowledge that one must stack two or three logs together in order to make it easier to get any one of the logs to begin burning.
Accordingly, it is an object of the invention to provide a fireplace accessory constituting a device for enhancing the efficiency of combustion of various fuels, and especially those typically burned in fireplaces, and especially logs.
Also an object of the present invention is to provide such an accessory which allows a user to burn a single log in a most effective manner without having to resort to starting the fire with multiple logs or to keep adding logs to maintain combustion.
It is another object of the invention to provide an accessory of the character stated for directing heat of combustion from a normal zone of combustion, such as outwardly from a fireplace.
It is yet another object of the invention to provide an accessory of the character stated which, by virtue of its thermal characteristics, is itself of a heat-radiating character, whereby when heated by the combustion fuels, it becomes hot for emitting radiation therefrom outwardly from a zone of combustion.
Another object of the invention is the provision of an accessory of the character stated which allows far greater fireplace combustion efficiency for typical lignocellulosic fireplace fuels, by achieving the burning of off-gases released during the combustion of such fuels.
It is yet another object of the invention to provide an accessory of the character stated which may be utilized in existing fireplaces, without the need for modification thereof, and which similarly avoids the need for andirons, fire grates, etc. within the fireplace.
Another object of the invention is the provision of an accessory of the character stated which provides an improved pattern of radiation of heat from a fireplace into an adjacent room to extract a greater amount of heat from the fireplace than otherwise would be obtained.
Another object of the invention is the provision of an accessory of the character stated which provides enhanced comfort for room occupants.
An object of the present invention is also to provide a novel method and arrangement of igniting fuels as well as smoke, gases and volatiles which are released by such fuels when burned by the use of a unique ignition arch concept of the invention.
Among still other objects of the invention may be noted the provision of such a device which is extremely simply constructed, utilizing very few separate parts and elements to provide an easily, rapidly, and economically manufactured device, utilizing relatively low-cost, long-lasting materials.
Other objects will be in part apparent and in part pointed out hereinbelow.